group-array

Group array of objects into lists.


Keywords
array, group, item, list, nested, prop, properties, property
License
MIT
Install
npm install group-array@1.0.0

Documentation

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Group array of objects into lists.

Please consider following this project's author, Brian Woodward, and consider starring the project to show your ❤️ and support.

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Install

Install with npm:

$ npm install --save group-array

Usage

var groupArray = require('group-array');

Examples

var arr = [
  {tag: 'one', content: 'A'},
  {tag: 'one', content: 'B'},
  {tag: 'two', content: 'C'},
  {tag: 'two', content: 'D'},
  {tag: 'three', content: 'E'},
  {tag: 'three', content: 'F'}
];

// group by the `tag` property
groupArray(arr, 'tag');

results in:

{
  one: [
    {tag: 'one', content: 'A'},
    {tag: 'one', content: 'B'}
  ],
  two: [
    {tag: 'two', content: 'C'},
    {tag: 'two', content: 'D'}
  ],
  three: [
    {tag: 'three', content: 'E'},
    {tag: 'three', content: 'F'}
  ]
}

Group by multiple, deeply nested properties

// given an array of object, like blog posts...
var arr = [
  { data: { year: '2016', tag: 'one', month: 'jan', day: '01'}, content: '...'},
  { data: { year: '2016', tag: 'one', month: 'jan', day: '01'}, content: '...'},
  { data: { year: '2016', tag: 'one', month: 'jan', day: '02'}, content: '...'},
  { data: { year: '2016', tag: 'one', month: 'jan', day: '02'}, content: '...'},
  { data: { year: '2016', tag: 'one', month: 'feb', day: '10'}, content: '...'},
  { data: { year: '2016', tag: 'one', month: 'feb', day: '10'}, content: '...'},
  { data: { year: '2016', tag: 'one', month: 'feb', day: '12'}, content: '...'},
  { data: { year: '2016', tag: 'one', month: 'feb', day: '12'}, content: '...'},
  { data: { year: '2016', tag: 'two', month: 'jan', day: '14'}, content: '...'},
  { data: { year: '2016', tag: 'two', month: 'jan', day: '14'}, content: '...'},
  { data: { year: '2016', tag: 'two', month: 'jan', day: '16'}, content: '...'},
  { data: { year: '2016', tag: 'two', month: 'jan', day: '16'}, content: '...'},
  { data: { year: '2016', tag: 'two', month: 'feb', day: '18'}, content: '...'},
  { data: { year: '2017', tag: 'two', month: 'feb', day: '18'}, content: '...'},
  { data: { year: '2017', tag: 'two', month: 'feb', day: '10'}, content: '...'},
  { data: { year: '2017', tag: 'two', month: 'feb', day: '10'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'jan', day: '01'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'jan', day: '01'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'jan', day: '02'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'jan', day: '02'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'feb', day: '01'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'feb', day: '01'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'feb', day: '02'}, content: '...'},
  { data: { year: '2017', tag: 'three', month: 'feb', day: '02'}, content: '...'}
]

Pass a list or array of properties:

groupArray(arr, 'data.year', 'data.tag', 'data.month', 'data.day');

Results in something like this: (abbreviated)

{ '2016': 
   { one: 
      { jan: 
         { '01': 
            [ { data: { year: '2016', tag: 'one', month: 'jan', day: '01' },
                content: '...' },
              { data: { year: '2016', tag: 'one', month: 'jan', day: '01' },
                content: '...' } ],
           '02': 
            [ { data: { year: '2016', tag: 'one', month: 'jan', day: '02' },
                content: '...' },
              { data: { year: '2016', tag: 'one', month: 'jan', day: '02' },
                content: '...' } ] },
        feb: 
         { '10': 
            [ { data: { year: '2016', tag: 'one', month: 'feb', day: '10' },
                content: '...' },
              { data: { year: '2016', tag: 'one', month: 'feb', day: '10' },
                content: '...' } ],
           '12': 
            [ { data: { year: '2016', tag: 'one', month: 'feb', day: '12' },
                content: '...' },
              { data: { year: '2016', tag: 'one', month: 'feb', day: '12' },
                content: '...' } ] } },
     two: 
      { jan: 
         { '14': 
            [ { data: { year: '2016', tag: 'two', month: 'jan', day: '14' },
                content: '...' },
              { data: { year: '2016', tag: 'two', month: 'jan', day: '14' },
                content: '...' } ],
           '16': 
            [ { data: { year: '2016', tag: 'two', month: 'jan', day: '16' },
                content: '...' },
              { data: { year: '2016', tag: 'two', month: 'jan', day: '16' },
                content: '...' } ] },
        feb: 
         { '18': 
            [ { data: { year: '2016', tag: 'two', month: 'feb', day: '18' },
                content: '...' } ] } } },
  '2017': 
   { two: 
      { feb: 
         { '10': 
            [ { data: { year: '2017', tag: 'two', month: 'feb', day: '10' },
                content: '...' },
              { data: { year: '2017', tag: 'two', month: 'feb', day: '10' },
                content: '...' } ],
           '18': 
            [ { data: { year: '2017', tag: 'two', month: 'feb', day: '18' },
                content: '...' } ] } },
     three: 
      { jan: 
         { '01': 
            [ { data: { year: '2017', tag: 'three', month: 'jan', day: '01' },
                content: '...' },
              { data: { year: '2017', tag: 'three', month: 'jan', day: '01' },
                content: '...' } ],
           '02': 
            [ { data: { year: '2017', tag: 'three', month: 'jan', day: '02' },
                content: '...' },
              { data: { year: '2017', tag: 'three', month: 'jan', day: '02' },
                content: '...' } ] },
        feb: 
         { '01': 
            [ { data: { year: '2017', tag: 'three', month: 'feb', day: '01' },
                content: '...' },
              { data: { year: '2017', tag: 'three', month: 'feb', day: '01' },
                content: '...' } ],
           '02': 
            [ { data: { year: '2017', tag: 'three', month: 'feb', day: '02' },
                content: '...' },
              { data: { year: '2017', tag: 'three', month: 'feb', day: '02' },
                content: '...' } ] } } } }

About

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Running Tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test
Building docs

(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

$ npm install -g verbose/verb#dev verb-generate-readme && verb

Related projects

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Contributors

Commits Contributor
32 doowb
13 jonschlinkert
2 johlym
1 cperryk

Author

Brian Woodward

License

Copyright © 2019, Brian Woodward. Released under the MIT License.


This file was generated by verb-generate-readme, v0.8.0, on July 22, 2019.